1. Field of the Invention
This invention relates generally to a device which is mounted to the transom of a boat utilizing the boat's existing thru-hull livewell pump system for means of attachment, which intake extends rearwardly from the boat's transom and generally in the same plane as the boat's bottom surface as to deliver a filtered water supply to a boat's livewell pump system while the boat is moving across a body of water or while the boat is stationary.
2. Description of Prior Art
When fishing from a boat it is desirable to keep caught fish and baitfish alive as well as keeping the boat's livewell pump operational throughout the entire fishing day. Keeping caught fish alive gives the food angler the best tasting fillets. Lively bait allows the fisherman the greatest chance at catching fish. For the sports angler, keeping caught fish alive generally is a requirement in order to qualify for prize money in fishing contests.
One method used for keeping caught fish alive is to place them in a net or perforated container and then lower them over the side of a fishing boat and attach them by a rope or chain. This method is undesirable due to the strain on the fisherman pulling this in and out of the water and also killing the fish while moving from spot to spot as the fish will have to be removed from the body of water and then placed into the boat while the boat is underway.
Another method invented to keep caught fish alive while allowing the boat to be mobile is called the "livewell". The livewell is a reservoir built into the boat's structure, which water is pumped into from a body of water and discharged through an overflow and back into the body of water replenishing the oxygen that is used up by the caught fish or bait.
The basic livewell generally consists of a thru-hull style pump, which threaded intake stem generally is mounted through the transom of the boat and is held secure using the livewell pump nut. From the discharge of the pump, a hose is connected and is channeled through the boat's structure to the livewell spray nozzle inside the top of a livewell reservoir, a master drain hose leads from the bottom of the livewell to the outside of the boat, and an overflow drain leading from the topside of the livewell to the outside of the boat. In operation, when the fishing boat is stationary in a body of water the intake stem on the transom of a boat is below the surface of the water. The pump is turned on and forces fresh water through the spray nozzle and into the livewell where the caught fish are stored. Water is kept at a predetermined level by installing a plug in the master drain causing the incoming water to rise to the point in which it flows out of the overflow drain at the top of the livewell. To drain the system, one pulls the plug in the master drain causing the livewell water to flow out of the livewell to the outside of the boat.
A disadvantage of the conventional livewell is that such livewell configurations do not operate when the fishing boat is moving at navigational speeds. As a boat starts to move through the water it begins to rise forming a trough behind the boat, which causes the transom mounted pump intake to no longer contact the body of water. Thus, when the boat is moving, the thru-hull pump intake is not submerged and no fresh surface water can be pumped into the livewell system.
Another disadvantage of the conventional livewell pump system is a condition termed "pump airlock." This is caused when the supply of water into the thru-hull pump intake is not adequate, such as when the thru-hull pump intake rises above the surface water level or when rough water conditions cause the thru-hull pump intake to be exposed to air, causing a pocket of air to develop in the pump impeller chamber, causing the thru-hull pump to loose its prime and become airlocked. Once an airlock develops, the pump will not pump water. This is frustrating to a fisherman because he has to interrupt his fishing to get the pump primed and operational again for his fish and bait to stay lively.
Another method invented for supplying water to fish when the boat is moving is the high pressure depending ram system. The ram system consists of a scoop type apparatus which extends below the bottom surface of a boat, a hose is fitted to the device and channeled direct to the livewell reservoir or to the livewell pump intake. One type system for reference is U.S. Pat. No. 5,279,246.
One disadvantage of these Ram type systems is that they deliver a high pressure forced water supply into the livewell pump assembly causing possible seal damage and unwanted water entering the hull.
Another disadvantage is they are generally difficult to install requiring additional holes to be drilled through the boat's hull or transom and also requiring the boat's inside structure to be dismantled in order to channel the hose into the livewell reservoir.
Two other disadvantages of Ram type systems involve the mounting of the water intake components on the transom or bottom of the boat. First, the scoop extends below the bottom surface of the boat in such a way as to cause cavitation to the boat's inboard or outboard motor, meaning they create a drag or plowing of the water as it passes under the boat. This turbulence greatly affects the boat's high speed performance. Second, the way in which the scoops are designed that when mounted in use, debris common to all bodies of water foul the intake scoop, thus preventing the aeration of the boat's livewell reservoir.